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51.
Change in Some Properties of Fats During Deodorisation The influence of deodorisation on some of the properties of fats was studied. Temperatures above 200°C were the deciding factors influencing the consistency and the compositions of triglycerides. The changes due to temperature play an important role in the preparation of fats for use in margarine manufacture. The results reported here were confirmed by DTA.  相似文献   
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Let μ be a measure supported on a compact connected subset of an Euclidean space, which satisfies a uniform d-dimensional decay of the volume of balls of the type
(1)  相似文献   
53.
Two donor–acceptor copolymers containing perylene diimide and oligothiophenes linked through triple bonds have been designed and synthesized by palladium catalyzed Sonogashira coupling reaction. The introduction of the triple bond spacer between the electron acceptor perylene moieties and the electron donating oligothiophene moieties produces an extended conjugation along the main chain, and produces soluble and high molecular weight copolymers.The thermal, optical and electrochemical properties of these copolymers were examined. The HOMO–LUMO energy levels of these copolymers, along with the quenching of their photoluminescence in 1:1 (w/w) blends with poly(3-hexylthiophene) (P3HT), indicate that they are suitable materials for application as electron acceptor and n-type components in bulk heterojunction solar cells with P3HT.  相似文献   
54.
We review computational intelligence methods of sensory perception and cognitive functions in animals, humans, and artificial devices. Top-down symbolic methods and bottom-up sub-symbolic approaches are described. In recent years, computational intelligence, cognitive science and neuroscience have achieved a level of maturity that allows integration of top-down and bottom-up approaches in modeling the brain. Continuous adaptation and teaming is a key component of computationally intelligent devices, which is achieved using dynamic models of cognition and consciousness. Human cognition performs a granulation of the seemingly homogeneous temporal sequences of perceptual experiences into meaningful and comprehensible chunks of concepts and complex behavioral sehemas. They are accessed during action selection and conscious decision making as part of the intentional cognitive cycle. Implementations in computational and robotic environments are demonstrated.  相似文献   
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Recent observations suggest that insulin increases cellular levels of activated, GTP-bound Ras protein. We tested whether the acute actions of insulin on hexose uptake and glucose-transporter redistribution to the cell surface are mimicked by activated Ras. 3T3-L1 fibroblasts expressing an activated mutant (Lys-61) N-Ras protein exhibited a 3-fold increase in 2-deoxyglucose uptake rates compared with non-transfected cells. Insulin stimulated hexose uptake by approximately 2-fold in parental fibroblasts but did not stimulate hexose uptake in the N-Ras61K-expressing fibroblasts. Overexpression of N-Ras61K also mimicked the large effect of insulin on 2-deoxyglucose transport in 3T3-L1 adipocytes, and again the effects of the two agents were not additive. Total glucose transporter protein (GLUT) 1 was similar between parental and N-Ras61K-expressing 3T3-L1 fibroblasts or adipocytes, whereas total GLUT-4 protein was actually lower in the N-Ras61K-expressing compared with parental adipocytes. However, expression of N-Ras61K in 3T3-L1 adipocytes markedly elevated both GLUT-1 and GLUT-4 in plasma membranes relative to intracellular membranes, and insulin had no further effect. These modulations of glucose transporters by N-Ras61K expression are not due to upstream regulation of insulin receptors because receptor tyrosine phosphorylation and association of phosphatidylinositol 3-kinase with tyrosine-phosphorylated proteins were unaffected. These results show that activated Ras mimics the actions of insulin on membrane trafficking of glucose transporters, consistent with the concept that Ras proteins function as intermediates in this insulin signaling pathway.  相似文献   
57.
We compared the psychometric adequacy of a multidimensional self-report battery for use with cognitively able, elderly adults under conditions of microcomputer and interviewer administration. The SENOTS battery contains scales of Happiness/Depression, Financial Hardship, Physical Symptoms, Activity Limitation, and Activity Propensity. The SENOTS microcomputer program contains sequential phases intended to (a) select out respondents incapable of interacting adequately with the microcomputer, (b) train respondents to make appropriate keyboard responses, (c) administer the program, and (d) store and process the responses. The SENOTS battery was administered to 80 community residents and 80 institution residents by either a microcomputer or an interviewer. Results indicated a comparable psychometric adequacy to the SENOTS battery under both administration conditions. Internal consistencies were all at acceptable levels, and the scales differentiated the community residents from the institution residents. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This review of the 1956–1977 literature concerning psychological well-being in the aged is limited to multidimensional approaches to the construct. The major research issues include the diverse conceptualizations of well-being by various experimenters, the differences in the experimental procedures employed by such investigators, and the relationship between well-being and a host of related variables such as activity level, personality, and health. It is concluded that a narrow conceptualization of well-being in terms of "current happiness" and the use of longitudinal as opposed to cross-sectional studies would lead to a better understanding of the relationship between well-being and other variables affecting the well-being of the aged. (58 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
60.
There are many methods of calculating the properties of lubricated hydrodynamic sliding bearings running at variable loads, but, in some cases, sliding bearings of heavy‐duty machines run under constant load and at variable speeds; this can lead to reduced film thickness in the bearing and boundary lubrication. The minimum oilfilm thickness in such a bearing needs to be calculated so that the proper lubricant viscosity can be selected to reduce solid‐solid contact during machine operation. In this study, a method is presented for calculating the film thickness of sliding bearings operating with alternating rotational directions. The results of the calculations show that the squeeze effect can develop enough load‐carrying capacity to prevent solid‐solid contact between the rubbing surfaces during operation, provided the change of direction of rotation is quick enough.  相似文献   
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